This paper describes a virtual environment, which can present dynamic force transformation during the control of objects. A 5-DOF haptic interface with the capability to generate kinesthetic effect is combined. In thi...This paper describes a virtual environment, which can present dynamic force transformation during the control of objects. A 5-DOF haptic interface with the capability to generate kinesthetic effect is combined. In this system, the operator manipulates an object in a virtual environment by using the 5-DOF master arm. When contacting with the virtual object, the contact force can be calculated and shown in the graphic interface. The contact response and deformation of the virtual object, which are usually called haptic rendering, also can be performed. The study supplies an approach to improve the operator’s immersion and can be used in many tele-robot control fields.展开更多
Progress is described regarding the development of a new electrotactile feedback glove designed for application to dexterous robot. The sensitivity of operator's finger against electrical stimulus pulse is conside...Progress is described regarding the development of a new electrotactile feedback glove designed for application to dexterous robot. The sensitivity of operator's finger against electrical stimulus pulse is considered. It is found that frequency, duty ratio, and voltage amplitude of electrical stimulus pulse determine the sensitivity of finger. The effects of materials, sizes, arrangements and shapes of electrodes on sensitivity of finger are analyzed. Finally, the tactile tele presence system is designed to experimentally confirm that the robot with electrotactile feedback glove can manipulate dexterous robotic multi fingered hand and identify and classify three sorts of objects.展开更多
To improve the accuracy and interactivity of soft tissue delormatlon simulation, a new plate spring model based on physics is proposed. The model is parameterized and thus can be adapted to simulate different organs. ...To improve the accuracy and interactivity of soft tissue delormatlon simulation, a new plate spring model based on physics is proposed. The model is parameterized and thus can be adapted to simulate different organs. Different soft tissues are modeled by changing the width, number of pieces, thickness, and length of a single plate spring. In this paper, the structural design, calcula- tion of soft tissue deformation and real-time feedback operations of our system are also introduced. To evaluate the feasibility of the system and validate the model, an experimental system of haptic in- teraction, in which users can use virtual hands to pull virtual brain tissues, is built using PHANTOM OMNI devices. Experimental results show that the proposed system is stable, accurate and promising for modeling instantaneous soft tissue deformation.展开更多
Cyanea nozakii Kishinouye (C. nozakii), a giant cnidarian of the class Scyphomedusae, order Semaeostomeae and family Cyaneidae, is widely distributed in the East China Sea, the Yellow Sea and the Bohai Sea, and is a...Cyanea nozakii Kishinouye (C. nozakii), a giant cnidarian of the class Scyphomedusae, order Semaeostomeae and family Cyaneidae, is widely distributed in the East China Sea, the Yellow Sea and the Bohai Sea, and is abundant from late summer to early autumn. Venom produced by C. nozakii during mass agglomerations can contaminate seawater resulting in death of the halobios and seriously damage commercial fisheries. Swimmers and fishermen commonly suffer painful stings from this j ellyfish, resulting in local edema, tingling, breathing difficulties, depressed blood pressure and even death. Such effects arise from the complex mixture of biologically active molecules that make up jellyfish venom. In the present study, the hemolytic activity of venom from tentacles of C. nozakii and factors affecting its activity were assayed. The HUso (defined as the amount of protein required to lyse 50% of erythrocytes) of the venom against dove and chicken erythrocytes was 34 and 59 gg/mL, respectively. Carboxylmethyl chitosan and glycerol could increase hemolytic activity at concentrations greater than 0.06% and 0.2 mol/L, respectively.展开更多
The modelling and simulation of deformable objects is a challenging topic in the field of haptic rendering between human and virtual environment.In this paper,a novel and efficient layered rhombus-chain-connected hapt...The modelling and simulation of deformable objects is a challenging topic in the field of haptic rendering between human and virtual environment.In this paper,a novel and efficient layered rhombus-chain-connected haptic deformation model based on physics is proposed for an excellent haptic rendering.During the modelling,the accumulation of relative displacements in every chain structure unit in each layer is equal to the deformation on the virtual object surface,and the resultant force of corresponding springs is equivalent to the external force.The layered rhombus-chain-connected model is convenient and fast to calculate,and can satisfy real-time requirement due to its simple nature.Simulation experiments in virtual human liver based on the proposed model are conducted,and the results demonstrate that our model provides stable and realistic haptic feeling in real time.Meanwhile,the display result is vivid.展开更多
In the underwater environment, many visual sensors don’t work, and many sensors which work well for robots working in space or on land can not be used underwater. Therefore, an optical fiber slide tactile sensor was ...In the underwater environment, many visual sensors don’t work, and many sensors which work well for robots working in space or on land can not be used underwater. Therefore, an optical fiber slide tactile sensor was designed based on the inner modulation mechanism of optical fibers. The principles and structure of the sensor are explained in detail. Its static and dynamic characteristics were analyzed theoretically and then simulated. A dynamic characteristic model was built and the simulation made using the GA based neural network. In order to improve sensor response, the recognition model of the sensor was designed based on the ‘inverse solution’ principle of neural networks, increasing the control precision and the sensitivity of the manipulator.展开更多
Objective To evaluate the effects of preoperative soft contact lens (SCL) wear on higher-order aberrations(HOAs)correction after wavefront-guided and conventional laser in situ keratomileusis (LASIK). Methods A prospe...Objective To evaluate the effects of preoperative soft contact lens (SCL) wear on higher-order aberrations(HOAs)correction after wavefront-guided and conventional laser in situ keratomileusis (LASIK). Methods A prospective randomized double-masked comparative study was conducted in 180 eyes of 90 patients scheduled for LASIK, including 92 eyes of 46 patients with previous SCL wear. The patients were divided into four groups: no SCL-conventional group, SCL-conventional group, no SCL-wavefront group and SCL-wavefront group. Preoperative and postoperative examinations included uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), contrast sensitivity and HOAs. Results The UCVA and BSCVA were 20/20 in all patients at 6 months postoperatively. And 36.3%, 22.7%, 18.1% and 35.4% gained one line or more of BSCVA in no SCL-wavefront group, SCL-wavefront group, no SCL-conventional group and SCL-conventional group, respectively. Both the safety index and efficacy index surpassed one in 4 groups and were highest in no SCL-wavefront group. The increase in root-mean-square (RMS) values of HOAs was significantly lower in no SCL-wavefront group and higher in SCL-wavefront group. At 6 months postoperatively, the increase in RMS of HOAs (RMSh) were 0.67, 1.58, 1.17 and 1.28 in no SCL-wavefront group, SCL-wavefront group, no SCL-conventional group and SCL-conventional group, respectively. Conclusion Preoperative contact lens wear has significant influence on the efficacy of HOAs correction in wavefront-guided LASIK. Patients with contact lens wear preoperatively should be cautious when scheduled for wavefront-guided LASIK.展开更多
By analyzing several effective finger practices, it is possible to consolidate the basic skills to help students adjust and establish a good touch mode. This is an important pre-requisite for pursuing strength and spe...By analyzing several effective finger practices, it is possible to consolidate the basic skills to help students adjust and establish a good touch mode. This is an important pre-requisite for pursuing strength and speed during playing. The training method can be targeted to solve some common problems, and guide students to consciously feel the touch and the change of tone, listening with ears, controlling with fingers to achieve solid and soft balanced unity.展开更多
文摘This paper describes a virtual environment, which can present dynamic force transformation during the control of objects. A 5-DOF haptic interface with the capability to generate kinesthetic effect is combined. In this system, the operator manipulates an object in a virtual environment by using the 5-DOF master arm. When contacting with the virtual object, the contact force can be calculated and shown in the graphic interface. The contact response and deformation of the virtual object, which are usually called haptic rendering, also can be performed. The study supplies an approach to improve the operator’s immersion and can be used in many tele-robot control fields.
文摘Progress is described regarding the development of a new electrotactile feedback glove designed for application to dexterous robot. The sensitivity of operator's finger against electrical stimulus pulse is considered. It is found that frequency, duty ratio, and voltage amplitude of electrical stimulus pulse determine the sensitivity of finger. The effects of materials, sizes, arrangements and shapes of electrodes on sensitivity of finger are analyzed. Finally, the tactile tele presence system is designed to experimentally confirm that the robot with electrotactile feedback glove can manipulate dexterous robotic multi fingered hand and identify and classify three sorts of objects.
基金Supported by the National High Technology Research and Development Programme of China(No.2013AA010803,2009AA01Z311,2009AA01Z314)the National Natural Science Foundation of China(No.61304205,61203316,61272379,61103086,41301037)+3 种基金the Natural Science Foundation of Jiangsu Province(BK20141002)the Open Funding Project of State Key Laboratory of Virtual Reality Technology and Systems,Beihang University,Jiangsu Ordinary University Science Research Project(No.13KJB120007)Innovation and Entrepreneurship Training Project of College Students(No.201410300153,201410300165)the Excellent Undergraduate Paper(design)Supporting Project of NUIST
文摘To improve the accuracy and interactivity of soft tissue delormatlon simulation, a new plate spring model based on physics is proposed. The model is parameterized and thus can be adapted to simulate different organs. Different soft tissues are modeled by changing the width, number of pieces, thickness, and length of a single plate spring. In this paper, the structural design, calcula- tion of soft tissue deformation and real-time feedback operations of our system are also introduced. To evaluate the feasibility of the system and validate the model, an experimental system of haptic in- teraction, in which users can use virtual hands to pull virtual brain tissues, is built using PHANTOM OMNI devices. Experimental results show that the proposed system is stable, accurate and promising for modeling instantaneous soft tissue deformation.
基金Supported by the National Natural Science Foundation of China(Nos.41376004,41406152)the Key R&D program of Shandong Province(Nos.2015GSF115022,2015GSF115034)the China Postdoctoral Science Foundation(No.2013M531654)
文摘Cyanea nozakii Kishinouye (C. nozakii), a giant cnidarian of the class Scyphomedusae, order Semaeostomeae and family Cyaneidae, is widely distributed in the East China Sea, the Yellow Sea and the Bohai Sea, and is abundant from late summer to early autumn. Venom produced by C. nozakii during mass agglomerations can contaminate seawater resulting in death of the halobios and seriously damage commercial fisheries. Swimmers and fishermen commonly suffer painful stings from this j ellyfish, resulting in local edema, tingling, breathing difficulties, depressed blood pressure and even death. Such effects arise from the complex mixture of biologically active molecules that make up jellyfish venom. In the present study, the hemolytic activity of venom from tentacles of C. nozakii and factors affecting its activity were assayed. The HUso (defined as the amount of protein required to lyse 50% of erythrocytes) of the venom against dove and chicken erythrocytes was 34 and 59 gg/mL, respectively. Carboxylmethyl chitosan and glycerol could increase hemolytic activity at concentrations greater than 0.06% and 0.2 mol/L, respectively.
基金Supported by the National High Technology Research and Development Programme of China(2013AA010803,2009AA01Z311,2009AA01Z314)the National Natural Science Foundation of China(61304205,61075068,61203316)+1 种基金the open funding project of State Key Laboratory of Virtual Reality Technology and Systems,Beihang University,Jiangsu Ordinary University Science Research Project(11KJB460006)Innovation and Entrepreneurship Training Project of College Students(201210300022,12CX023,201310300092)
文摘The modelling and simulation of deformable objects is a challenging topic in the field of haptic rendering between human and virtual environment.In this paper,a novel and efficient layered rhombus-chain-connected haptic deformation model based on physics is proposed for an excellent haptic rendering.During the modelling,the accumulation of relative displacements in every chain structure unit in each layer is equal to the deformation on the virtual object surface,and the resultant force of corresponding springs is equivalent to the external force.The layered rhombus-chain-connected model is convenient and fast to calculate,and can satisfy real-time requirement due to its simple nature.Simulation experiments in virtual human liver based on the proposed model are conducted,and the results demonstrate that our model provides stable and realistic haptic feeling in real time.Meanwhile,the display result is vivid.
文摘In the underwater environment, many visual sensors don’t work, and many sensors which work well for robots working in space or on land can not be used underwater. Therefore, an optical fiber slide tactile sensor was designed based on the inner modulation mechanism of optical fibers. The principles and structure of the sensor are explained in detail. Its static and dynamic characteristics were analyzed theoretically and then simulated. A dynamic characteristic model was built and the simulation made using the GA based neural network. In order to improve sensor response, the recognition model of the sensor was designed based on the ‘inverse solution’ principle of neural networks, increasing the control precision and the sensitivity of the manipulator.
文摘Objective To evaluate the effects of preoperative soft contact lens (SCL) wear on higher-order aberrations(HOAs)correction after wavefront-guided and conventional laser in situ keratomileusis (LASIK). Methods A prospective randomized double-masked comparative study was conducted in 180 eyes of 90 patients scheduled for LASIK, including 92 eyes of 46 patients with previous SCL wear. The patients were divided into four groups: no SCL-conventional group, SCL-conventional group, no SCL-wavefront group and SCL-wavefront group. Preoperative and postoperative examinations included uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), contrast sensitivity and HOAs. Results The UCVA and BSCVA were 20/20 in all patients at 6 months postoperatively. And 36.3%, 22.7%, 18.1% and 35.4% gained one line or more of BSCVA in no SCL-wavefront group, SCL-wavefront group, no SCL-conventional group and SCL-conventional group, respectively. Both the safety index and efficacy index surpassed one in 4 groups and were highest in no SCL-wavefront group. The increase in root-mean-square (RMS) values of HOAs was significantly lower in no SCL-wavefront group and higher in SCL-wavefront group. At 6 months postoperatively, the increase in RMS of HOAs (RMSh) were 0.67, 1.58, 1.17 and 1.28 in no SCL-wavefront group, SCL-wavefront group, no SCL-conventional group and SCL-conventional group, respectively. Conclusion Preoperative contact lens wear has significant influence on the efficacy of HOAs correction in wavefront-guided LASIK. Patients with contact lens wear preoperatively should be cautious when scheduled for wavefront-guided LASIK.
文摘By analyzing several effective finger practices, it is possible to consolidate the basic skills to help students adjust and establish a good touch mode. This is an important pre-requisite for pursuing strength and speed during playing. The training method can be targeted to solve some common problems, and guide students to consciously feel the touch and the change of tone, listening with ears, controlling with fingers to achieve solid and soft balanced unity.